A reporter’s access to the scene of a newsworthy event usually depends on the type of property -- public, private, or "nonpublic" government property -- to which access is sought. Public property restrictions are generally limited to reasonable time, place and manner regulations, while private property owners have much more control over access.
Reporters don't have a greater right of access to prisoners than the general public. Police often allow journalists to obtain credentials to cover crime and disaster scenes. There are also often limits on access to public buildings and election polling places.